cost of building a 6m by 5.5M rear extension

[mandm65]

Guys
I am trying to estimate the cost of building a 6m by 5.5M rear extension.
For a start just like to know the ballpark figure for the followings, would be grateful for your input.
Cheers

Foundations/Damp course, (3 sides), Average depth.
Labour
Material

Brickwork (including insulation) 3 Meter high wall (two sides third will be bi-folding door)
Labour
Material

Flat Roof (6m by 5.5M) Glassfibre
Labour
Material

Floor (including insulation)
Labour
Material

Inspection chamber relocation (approx. 7 Meter out and 6Meter back)
Labour
Material

 

[tony1851]

Do you seriously expect people to sit down and take time to do a breakdown of the figures for you for free?

 

[mandm65]

Do you seriously expect people to sit down and take time to do a breakdown of the figures for you for free?

No I dont, its targeted for individuals who have some idea/exprience!
I would be happy if someone could give me a ballpark multiplier, thats all.

 

[Blagard]

Suggest you pick and chose the things you are doing here -> Cost Guide

 

[tony1851]

Suggest you pick and chose the things you are doing here -> Cost Guide

Who needs Quantity Surveyors now!

 

[Jasonm1790]

If you allow £1000/sq.m for the whole job you should be somewhere close.